20-11-2012, 04:00 PM
NANOTECHNOLOGY FOR WATER TREATMENT
NANOTECHNOLOGY FOR WATER TREATMENT.pptx (Size: 610.72 KB / Downloads: 45)
NANOTECHNLOGY
Deals with manufacturing or manipulation of materials at nanoscale(10-9m). Has applications in many different fields, like electronics, medical, energy sector, environmental remediation. Being evaluated in water treatment processes in recent years Materials having nanoscale dimensions referred to as Nanomaterials.
NANOPARTICLES
Metallic, ceramic or inorganic.
Dimensions 1-100nm.
Large surface area, very reactive.
Exhibit interesting mechanical, magnetic, optical, chemical properties.
NANOMATERIALS IN WATER TREATMENT SYSTEMS
Made of carbon nanotubes.
Pore size: 0.0001-0.001μm.
Can remove virus, bacteria, suspended solids, large multivalent ions, dissolved organics, herbiscides, pesticides etc.
Greater efficiency compared to microfilters and ultrafilters.
Energy usage – Low.
Operating cost – Rs. 10-20 per 1000 liters.[2]
Useful in desalination operations. Being used for desalination in Israel & certain U.S. Municipalities notably Long Beach, California Municipal Water District.[1]
.Nanosorbents:
Used majorly in water remediation. For removing inorganic and organic pollutants, from contaminated water.
Nanoparticles used as sorbents.
Nanoparticles can be functionalized with various chemical groups to increase their affinity towards target compounds.
Nanocrystalline zeolites can remediate water containing cationic species such as ammonium and heavy metals. As well chemicals like 137Cs and 90Sr. [5].
Magnetic nanoparticles bind with contaminants , such as oil and arsenic and removed using a magnet.